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7 January 3, 1913 

USE OF FINGER BOWLS. 

AN OBJECTIONABLE CUSTOM AS SOMETIMES PRACTICED. 

A Note by C. H. Lavinder, Surgeon, United States Public Health Service. 

A recent bulletin of the service (Public Health Bulletin No. 57) 
reviews the subjects of common drinking cups and roller towels, 
and gives the laws relating thereto. Neither in this bulletin nor else- 
where have I ever seen any reference to an abuse which it seems to me 
is of little less importance than the common drinking cup, and the 
dangers from which are of quite a similar character. This is the use 
of the common finger bowl. 

It seems to be customary even in high-class restaurants to have in 
use about half a dozen finger bowls, more or less, and these do service 
for many patrons. The water in them seems to be changed at rare 
intervals and entirely in the discretion of the waiter. Occasionally 
one will see the old water poured out and fresh poured in, but far 
more frequently even this is not done. I presume the bowls must 
be taken out and washed occasionally. Now, when one considers 
that many persons in using these bowls wash not only their fingers but 
their lips as well, it would seem that the conditions of the common 
drinking cup are different only in degree. Moreover with the finger 
bowl it is not only the question of using a common bowl but often 
common water also. 

Since I first noticed in some hotels and restaurants this disgusting 
manner of serving these convenient accessories of a table service, I 
have taken some pains to learn how widespread such a thing might be, 
and my observations lead me to the belief that it is very common 
indeed. I am inclined to think that the common finger bowl should 
be classed with the common drinking cup, as an offense of the same 
character, but possibly less in degree. 



HOOKWORM DISEASE. 

PROPORTION OF MALES TO FEMALES IN THE AMERICAN HOOKWORM (NECATOR 
AMERICANUS), BASED ON 13,080 WORMS FROM 102 CASES.i 

By Ch. Waedeli. Stiles, Professor of Zoology, and W. L. Altman, Assistant, Hygienic Laboratory, 
United States Public Health Service. 

The point was raised by Leichtenstern in 1885 that by counting 
the male and female hookworms passed by a patient and drawing 
the proportion, the clinician has a practical clue to the completeness 
or incompleteness of the cure effected. This point was based upon 
the premises that the males and the females are present in relatively 
fairly constant proportion and that the males are more difficult to 
expel than are the females. 

1 Read at the XV International Congress on Hygiene and Demography, Washington, September, 1912. 



.Tnnuaiy 3, lOKi 



This view of Leichtenstern, based upon the Old World hookworm 
(Ancylostoma duodenale), appears to be one that might in certain 
cases be of practical importance, and it seemed wise, therefore, to test 
it as applied to our American hookworm. 

The opinion seems to prevail that in case of Ancylostoma duo- 
denale the female worms are much more numerous than the males. 
Bearing on this point the following data are found in our notes 
(absence from library facilities at present prevents us from consult- 
ing some of the original articles) : 

Bilharz (1853, 55), Heller (1876b, 778), and R. Blanchard (1888a, 
765) report 1 male to 3 females. White (1867, 427) states that the 
males are less numerous than the females. The following cases are- 
reported with the number of males and females passed: 





Number of — 




Author. 










Cases. 


Worm**. 


Mates. 


Females. 






109 


38 


131 


Leichtenstern, 1885, 501. 




45 


10 


35 


Do. 




306 


83 


223 


Do. 




695 


235 


460 


Leichtenstern, 1885, 501, Schumacher's case. 




142 





142 


Leichtenstern, 1886, 217, Schulthess's case. 




647 


188 


459 


Do. 




64 


13 


51 


Do. 




250 





250 


Do. 




153 


1 


152 


Do. 




135 


20 


115 


Do. 




230 


8 


222 


Do. 


11 


2, 836 


596 


2,240 





In the foregoing 11 cases it is clear that the females (78 per cent) 
are in excess of the males (21 per cent). In 7 cases from Schulthess 
the females and males were about 6 to 1. 

Leichtenstern (1886, 216-217) quotes two series of cases from 
Schulthess, as follows: 



Number of — 


Cases, i Worms. 


Males. 


Females. 


26 

(?) 


6, 134 
4,111 


1,811 
1.367 


4,323 
2,744 


26+ 


10,245 


3,178 
31 percent. 


7,067 
08 per cent. 



In these two series also it is clear that the females (68 per cent) 
are in excess of the males (31 per cent). In the series of 26 cases 
the variation was between 10 males to 360 females and 10 males to 
11 females. 

Leichtenstern remarks that the males may roll themselves up in 
the feces and be overlooked. He also states that cases occur in 



9 



January 3. 1913 



which only the females appear for two days after the anthelmintic; 
then the males appear. 

From the foregoing statistics, based upon Ancylostoma duodenale, 
we were prepared to find similar conditions in the case of Necator 
americanus, especially since Lutz (who probably had Necator before 
him) is quoted as reporting for 3,000 worms a proportion of 3 females 
to 2 males. 

In hospital work we usually have hookworm patients under obser- 
vation only one day per week. It becomes necessary to inquire, 
therefore, into the number and proportion of worms passed in suc- 
cessive stools and on successive days in order to have an indication 
of the proportion of worms that escape collection on the day of 
treatment. 

Number of worms and proportion of sexes found in successive stools 
on day of thymol treatment. — The stools may follow each other so 
slowly or so rapidly, namely, so ununiformly, that a tabulation by 
actual stools has been followed in only a very few instances. 

Case .No. 3 (age 21 years) of our 1911 series shows the following 
data on day of treatment; dose, 45 grains of thymol: 





Stool. 


Males. 


Females. 


Total. 


First 


29 

(?) 




4 

CO 
1 


33 




01 


Third 


1 










29+ 


5+ 


95 







Although in the second stool the males and the females were not 
separated, it is clear that in the first stool the males were greatly in 
excess of the females, and therefore that they were not more difficult 
to expel. 

Case No. 63 (age 16) of our 1911 series shows the following data on 
first treatment; dose, 10 grains of thymol. (The patient had received 
one treatment before he came to the marine hospital.) 



Date and number of stool. 


Males. 


Females. 


Total 
worms. 




Number. 


Per cent. 


Numl>er. 


Per cent. 


01347. 


Aug. 4: 

First 


1 

.50 
4S 
18 
21 

13 
2 


50 

39.6 

44 

60 

36.8 

68 
50 


1 
76 
61 
12 
36 

6 
2 


50 

60.3 

55 

40 

63 

31 
50 


2 

126 

109 

30 

57 

19 
4 


0.57 




36.3 


Third 


31.4 




8.6 


Fifth 


16.4 


Aim. 5: 

Sixth 


5.4 




1.1 






Total 


153 


44 


194 


55 


347 


100.00 







January 3, 1913 10 

In this treatment it is clear (a) that the female worms were in 
excess of the males for the total treatment (7 stools) and for stools 
Nos. 2, 3, and 5; (6) that the males and females were equal in stools 
Nos. 1 and 7; and (c) that the males were in excess in stools Nos. 4 
and 6. 

The two cases cited do not seem to give us any clue of practical 
value in use of statistical data as to sexes in their order of expulsion 
in a given treatment. 

In our notes we find two literature references for comparison. 
E. Parona, according to E. Blanchard (1888a, 765) reports a case as 
follows: First stool contained 8 males and 104 females, total 112 
worms; second stool contained 16 males and 19 females, total 35 
worms; third stool contained 107 males and 66 females, total 173 
worms. 

Blanchard (1888a, 765) also reports a case from Leichtenstern as 
follows: First stool contained 10 males and 124 females, total 134 
worms; second stool contained 28 males and 7 females, total 35 
worms. 

It is not clear to us whether Parona's case involved 3 courses of 
treatment or 3 stools after 1 course of treatment, but our notes give 
the following data for Leichtenstern's (1885, 101) case: First treat- 
ment, 15 extr. fil. mar., 1 first 4 days; 10 males and 124 females, total 
134 worms. Second treatment, 10 extr. fil. mar., 1 28 males and 
7 females, total 35 worms. Total, 38 males and 131 females. Grand 
total, 169 worms. 

Accordingly, positive data for comparison between Necator ameri- 
canus and Ancylostoma duodenale, in respect to the point under dis- 
cussion, are not available to us at present. 

Duration of passage of worms after thymol. — In hospital work the 
average hookworm patient is, as stated above, usually under obser- 
vation for only about 18 to 24 hours at a time. He is admitted to 
the wards late in the afternoon or early in the evening. He takes his 
thymol the next morning. By 1 to 4 o'clock in the afternoon he is 
over the effects of the salts and thymol to such an extent that he 
either desires to go home or from a financial (administrative) point of 
view there is little or no justification in retaining him longer. Accord- 
ingly, under ordinary circumstances, opportunity is presented to 
collect the worms passed only up to 3 or 5 p. m. of the day of treat- 
ment. While this permits, doubtless, the collection of most of the 
worms, a number escape the observer, for they continue to pass for 
three or four days or more, as the following cases show. 

1 German equivalent for Oleoresina aspidii of the United States pharmacopoeia. 



11 

CASE NO, 63. 



January 3. 101 ; 



Date. 



Thymol. 



Worms. 



Male. 



Num- 
ber. 



Per cent. 



Female. 



Total. 



Num- 
ber. 



Per cent of 
total of 

each treat- 
ment. 



Aug. 4 

Aug. 5 

Aug. 6 

Total 

Aug. 8 

Aug. 9 

Aug. 10. . . . 

Total 



Grains. 
10 





138 
15 
6 



42. 5 
65. 2 

22.2 



10 



159 



42,5 



25 





1X0 

8 
21 



57.5 
34.8 
77.8 



75 

100 





324 
23 

27 



(i 



SO 
20 




CASE NO. 170. 



Date. 



Thymol. 



Worms. 



Male. 



No. Per cent. 



Female. 



No. | Per cent 



Total. 



Per cent of total of 
each treatment. 



July3 

July 4 

July 5 

July6 

July7 

July 8 

Total 

July 21.... 
July 22.... 
July 23.... 
Julv24.... 
July 25.... 
July 26.... 

Total 

July 27.... 
July 28.... 
July 29.... 
July 30.... 
July 31.... 

Aug. 1 

Aug. 2 

Total 

Aug. 3 

Aug. 4 

Total 



Grains. 
15 









15 



25 



30 



30 



40 



43.1 


o 
o 






41.3 



41 
100 
50 


50 





44.4 



.50 



22.7 




25 




50 



23.3 



23 



35.3 




m 

100 




100 



58.7 



m 
o 

50 
100 

50 
100 



55. ii 



77.3 


100 
75 




50 



76.7 



64.7 




30 



95.6 per cent of 46. 
2.2 per cent of 46. 



2.2 per cent of 46. 



77.8 per cent of 90. 
4.4 per cent of 90. 
8.9 per cent of 90. 
1.1 per cent of 90. 
6.7 per cent of 90. 
1.1 per cent, of 90. 



73.3 per cent of 30. 

6.7 per cent of 30. 
13.3 per cent of 30. 



6.7 per cent of 30. 



100 per cenl of 17 



January 3, I9i:i 



12 



CASK NO. a»i. 





Thymol. 


Worms. 




Date. 


Males. 


Females. 


Total. 


Per cent of 

total of 
each treat- 




Num- 
ber. 


Per cent. 


Num- 
ber. 


Percent. 


ment. 


All);. 12 


Grains. 
45 


1) 



275 

7 
3 



46.8 


312 

fi 
7 



53.1 


587 

13 
10 



96.2 


Aug. 13 




Auk. 14 


53. 8 
30 


46.1 
70 


2.1 


Aug. 16 


1.6 










Total 


45 


285 


46.7 


325 


53.2 


610 


100 






A lip. 17 


45 






48 

n 
l 





52.7 


43 


2 

5 




47.2 


91 

3 




96.8 






Aug. 19 


33.3 


66.2 


3.1 


Aug. 20 




Aug. 21 
















Total 


45 


49 


52.1 


45 


47.8 


94 


100 






Aug. 22 


45 




10 

5 


47.6 


11 

1 


52.3 


21 

6 




Aug. 23 




Aug. 24 


83.3 


16.6 


99 9 






Total 


45 


15 


55.5 


12 


44.4 


27 


100 






A ug. 25 


45 







2 


100 


2 


100 









From the foregoing cases it is clear that all worms expelled by a 
given course of treatment need not necessarily be passed on the day 
of treatment, but while about 75 to 95 per cent of the specimens 
expelled may be passed within 12 hours after the drug is adminis- 
tered, worms may continue to pass for 5 or 6 days. 

It further seems evident from the foregoing records that the males 
and females do not follow any regular order in passing which can be 
used as a practical indication as to the completeness or incomplete- 
ness of the cure. 

Two practical conclusions are to be drawn from the foregoing data. 

(1) Since 75 to 95 per cent of the worms pass during the first 12 
hours after administration, all hospital records that give the number 
of worms collected during this period are subject to a theoretical error 
of about 5 to 33 per cent; that is to say, the actual number of worms 
passed may be from one-twentieth up to one-third larger than actu- 
ally reported. This point should be borne in mind when comparing 
statistics derived from treatment with statistics derived from autopsy 
not preceded by treatment. 

(2) It occasionally occurs that on the day of treatment not a single 
worm is collected, but later microscopic examination is negative. 
Probably the correct conclusion is that the worms have been passed 
after the patient has been discharged. 

Proportion of male and female hookworms passed after thymol treat- 
ment. — In nearly all of the following cases the worms were collected 



13 January 3, 1913 

within 12 hours (namely, by 6 p. m.) after the first dose of thymol 
(which is given at 6 a. m.). 

Two groups of cases, each with three subgroups, may be compared. 

In the first group are found 58 cured male cases, arranged in three 
subgroups according to the preponderance of male worms, equal num- 
ber of males and females, and preponderance of female worms. 

Of these 58 patients, 18 cases (or 31 per cent) showed more male 
(59 per cent) than female (40 per cent) hookworms; 5 cases (8 per 
cent) have an equal number of male and female worms; 35 cases 
(60 per cent) have an excess of females. Thus, on a basis of these 
cases, the chances are about 6 out of 10 that there will be an excess 
of females, but this percentage is not high enough to put to any 
practical account in determining, by counting the males and females 
collected, whether or not the patient is entirely freed from his worms. 
In fact, the labor involved would be much greater, more tedious, and 
more disagreeable than the labor involved in making a new micro- 
scopic examination a few days later. 

The 18 cases with an excess cf males showed 1,378 worms, 821 of 
which (or 59 per cent) were males, and 557 of which (or 40 per cent) 
were females. 

The 5 cases with equal number of male and female worms were all 
light infections, averaging only 11.6 worms each. 

The 35 cases with more females than males showed 6,524 ' worms, 
2,797 of which (or 43 per cent) were males, and 3,727 of which (or 
57 per cent) were females. 

Of the total 7,960 1 worms collected from the 58 cases, 3,647 speci- 
mens (or 45 per cent) were males, and 4,313 specimens (or 54 per 
cent) were females. 

In respect to number of worms present, the cases with equal males 
and females averaged the smallest number of worms (11), those with 
an excess of males came next (76), and those with an excess of 
females came next (186). The average was 137 worms. Thus, in 
general, the heaviest infections were those with the largest number of 
females, but this is not of much significance since only 9 of the 35 
female-excess cases were above the average (139) in number of 
worms present, while 2 of the 18 male-excess cases were above the 
average. 

The "cured" 2 cases are given in the following table. 

' I'lns 2(> worms, the sex of which was not determined. 

2 "Cured" menus that later mieroscopie examination was negative. 



Jauuary 3, 1913 



14 



Tabulation of 58 aired male hospital cases according to total number of worms and 
preponderance of sex of parasites. 

A. EIGHTEEN CASES WITH EXCESS OF MALES. 



Case No. 


Worms. 


Case No. 


Worms. 


Total. 


Males. 


Females. 


Total. 


Males. 


Females. 


Ill 


474 
143 
138 
111 
97 
95 
72 
68 
62 
42 


277 
74 
82 
65 
58 
68 
37 
36 
45 
31 


.197 
69 
56 
46 
39 
27 
35 
32 
17 
11 


31 


37 
9 

8 
7 
7 
6 
1 
1 


21 
6 
5 
6 
4 
4 
1 
1 


16 


26 


55 


3 


163 


139. 
58.. 




3 


11 




1 


144 


92 


3 


29 


73 


2 


66 


15 





67 


125 . 







Total (18).... 




165 . 


1,378 


1821 


! 557 







B. FIVE CASES WITH EQUAL MALES AND FEMALES. 



12.. 
53.. 

170. 
109. 



44 


22 


22 


6 


3 


3 


4 


2 


2 


2 


1 


1 



Total (5). 



' 29 



('. 35 CASES WITH EXCESS OF FEMALES. 



78 

110 


2,251 

1,142 

633 

538 

506 

295 

170 

107 

150 

113 

92 

80 

73 

72 

58 

28 

3 

,9 


1,049 

564 

234 

254 

173 

99 

77 

52 

43 

55 

10 

35 

27 

32 

24 

11 

9 

10 

6 


1,202 

578 

399 

284 

333 

196 

93 

115 

107 

58 

76 

45 

46 

40 

34 

17 

15 

11 

13 


80 

75 


17 

14 
11 

8 
7 
7 
6 
5 
4 
3 
3 
2 
2 
1 
1 
1 


4 
5 
5 
3 
3 
3 
2 
1 
1 









13 
9 


63 


52 


6 


39 


87 


5 


24 


90 


4 


23 


108 


4 


27 

41 


109 

93 


4 

4 


119 


13 

7 . 


3 


44 




83 


89 


3 


34 


172 

153 

91 

140 


2 


56 


2 


21 


1 


92 


1 


32 


88 


1 




Total (35).... 




157 


> 6,524 


5 2, 797 


6 3, 727 


74 









1 59 per cent. '■> 50 per cent. 

* 40 per cent. < Plus 26, sex not counted. 

D. SUMMARY OF 58 CUBED CASES. 



s 43 per cent, 
e 57 per cent. 







Cases. 


Total. 


Worms. 




Males. 


Females. 


A 


18 
5 
35 


1,378 

58 

16,524 


821 

29 

2,797 


557 


B 


29 














58 


17,960 


= 3,647 


M.313 







i Plus 26, sex of which was not determined 



2 45 per cent. 



3 54 per cent. 



For comparison with these 58 complete cures, 44 male hospital 
cases can be presented in connection with which it is either definitely 
known that later microscopic examination (in 1911) was positive 



15 



January 3, 1913 



(hence the cure was incomplete), or through failure to obtain speci- 
mens the completeness or incompleteness of the cure was left in doubt. 

Of these 44 cases, 19 patients (or 43 per cent) showed an excess of 
males; there was a total of 2,738 worms, 1,468 of which (or 53 per 
cent) were males and 1,270 of which (or 46 per cent) were females. 
These percentages are not very different from those of the corre- 
sponding cured cases. 

Of the 44 cases, 4 patients (or 9 per cent) showed an equal number 
of males and females. All were light infections, averaging only 10.5 
worms each. 

Of the 44 cases, 21 patients (or 47 per cent) showed an excess of 
females; of a total of 2,340 worms, 1,001 specimens (or 42 per cent) 
were males, and 1,339 specimens (or 57 per cent) were females. 

The cases in question are tabulated as follows: 



Tabulation of 44 male hospital cases, some with incomplete cure, some without final data 
as to cure, arranged according to total number of ivorms and preponderance of sex of 
parasites. 

A. NINETEEN CASES WITH EXCESS OF MALES. 



Case No. 


Worms. 


Case No. 


Worms. 


Total. 


Male. 


Female. 


Total. 


Male. 


Female . 


85 


710 
695 
366 
315 
172 
158 
85 
70 
58 
34 
20 


387 

353 

188 

163 

89 

82 

60 

39 

31 

29 

11 


323 

342 

178 

152 

83 

76 

25 

31 

27 

5 

9 


20.. 




11 
10 
9 
7 
5 
5 
5 
3 


6 
7 
5 
4 
5 
3 
3 
3 


5 


57 


46 


3 


94 


65 


4 


69 


115. 
95.. 




3 


141 







12 

9 


79 

97 


2 

2 


47 


145. 









Total (19).... 




3 

143 


2,738 


'1,468 


2 1,270 



B. F0IJK CASES WITH EQUAL MALES AND FEMALES. 



158 


18 
10 
10 


9 
5 
5 


9 
5 
5 


104 


4 


2 


2 


74 

ii8 


Total (4) 




42 


3 21 


3 21 







C. TWENTY-ONE CASES WITH EXCESS OF FEMALES. 



68 


366 
347 
315 
257 
256 
199 
170 
113 
93 
86 
39 
32 


158 
163 
128 
109 
125 
91 
62 
39 
43 
40 
13 
10 


208 
184 
187 
148 
131 
108 
108 
74 
50 
46 
26 
22 


72 


16 
15 

9 

7 
5 
4 
4 
4 
3 


7 
5 
3 
3 




1 
1 




9 


30 


35 


10 


45 


126 


6 


10 


33 


4 


99 


136 


5 


117 


105 


4 


16 


137 

6 


3 


2 


3 


1 


154 


3 




Total (21).... 




5 


2,340 


a, ooi 


5 1,339 


116 









1 53 per cent. 
! 46 per cent. 
3 50 per cent. 



< 42 per cent. 
5 57 per cent. 



January '6, 1913 



16 



Tabulation of 44 male hospital cases, some with incomplete cure, some without final data 
as to cure, arranged according to total number of worms and preponderance of sex of 
pcrasites — Continued. 



D. SUMMARY. 





Cases. 


Worms. 




Total. 


Male. 


Female. 




19 

4 

21 


2,738 

42 

2,340 


1,468 

21 

1,001 


1,270 


B 


21 




1,339 








44 


5,120 


'2,490 


2 2,630 





1 48 per cent. 



2 51 percent. 



Comparing these statistics with the sex statistics of the cured cases, 
it is not evident that the proportion of the sexes gives us any practical 
clue to the question whether our patient is or is not cured. 

Combining the two sets of statistics we have the following table: 

Table ofivorms, by sex, in lOt cases. 





Cases; 


Total. 


Male. 


Female. 


Average 




Number. 


Per cent. 


Number. 


Per cent. 


per case. 


Cured 


58 
44 


17,960 
5,120 


3,647 
2,490 


46 
48 


4,313 
2,630 


53 
51 


137 


Others 


116 






Total 


102 


1 13,080 


6,137 


46 


6,943 


53 


128 







i Plus 26 worms, sex of which was not determined. 

Proportion of male and of female worms passed in different treatments 
of 58 cases. — The following 58 cases of complete cures give data as to 
sex of parasites passed in successive treatments: 

A. FORTY-THREE CASES CURED IN ONE TREATMENT. 





•Age- 


Thymol. 


Worms collected. 


Case No. 


Total. 


Males. 


Females. 




Number. 


Per cent. 


Number. 


Per cent, 


134 


14 
24 

37 
14 
16 
23 

8 
10 
10. 

7 
13 
30 
20 
14 
12 


QroVns. 
25 
60 
60 
20 
30 
60 
10 
20 
20 
15 
25 
60 
45 
30 
30 




24 

97 

150 

3 

167 

42 

1 

19 

5 

1 

8 

72 

4 

7 




9 

58 

43 



52 

31 



6 

1 



5 

32 

1 

3 



37 
59 
28 


31 
73 




15 

39 

107 

3 

115 

11 





70 


62 


144 


40 


119 


73 


7. 


100 


41 


68 


165 


26 


91 


i 1 
31 I 13 
20 : 4 

o ; 1 

62 ! 3 
44 1 40 
25 j 3 
42 ! 4 


100 


74 : 


68 




80 


140 


100 


139 


37 


21 


55 




75 


90 


57 



17 January 3, 1913 

A. FORTY-THREE CASES CURED IN ONE TREATMENT— Continued. 





Age. 


Thymol. 




Worms collected. 


Case No. 


Total. 


Males. 


Females. 




Number. 


Per cent. 


Number. 


Per ceut. 




20 
12 
19 
14 
36 
25 
20 
11 
11 
13 
12 
9 
5 

60 
33 
7 
21 
13 
31 
9 
9 
14 
38 
16 
11 
20 
29 
21 


Grains. 
50 
25 
45 
25 
50 
45 

42.5 
25 
25 
25 
25 
20 
7.5 
50 
50 
15 
60 
20 
60 
20 
20 
30 
60 
20 
15 
45 
.0 
60 


7 

21 

37 

9 

58 

44 

6 

4 

2 

1 

6 

7 

1 

6 

8 

2 

95 

138 

17 

2 

3 

7,i 

2 

11 

80 

143 


6 

10 

21 

6 

24 

22 

4 

2 

1 

1 

2 

4 



3 

3 



68 

82 

4 





1? 

27 
1 
5 

35 

74 


85 
47 
57 
66 
41 
50 
06 
50 
50 
100 
33 
57 


50 
37 


71 
59 
23 




42 
39 
37 
50 
45 
43 
51 


1 

11 

16 

3 

34 

22 

2 

2 

1 



4 

3 

1 

3 

5 

2 

27 

50 

13 

2 

3 

4 

17 

46 

1 

6 

45 

69 


15 




52 




43 




33 




58 




59 




33 




50 




50 




e 




66 




42 


88 


10U 




50 


87 


02 




100 


29 


28 


163 


40 




76 


153 


100 


89 


100 


108 


57 




60 


56 


03 


62 


50 




£4 




50 


20 


48 














1,485 


1,418 


600 


40 i 758 


33 













B. SIX CASES CURED IN TWO TREATMENTS. 



75 


5 


10 
10 


13 

1 


4 
1 


30 
100 


9 



69 











20 


14 


5 


35 


9 


64 


67. 




12 


20 
20 


63 

5 


34 
2 


54 
40 


29 
3 


46 






60 




40 


68 


36 


53 


32 


47 






13 




11.. 


20 
25 


97 
14 


59 
6 


60 

42 


38 
8 


39 






57 




45 


111 


65 


58 


46 


41 






15 




110. 


25 
25 


1.094 
48 


539 
25 


49 
52 


555 
23 


50 






47 




50 


1.142 


564 


49 


578 


51 






18 




83.. 


50 
50 


S3 
9 


16 



19 



67 
9 


SO 






100 




100 


92 


16 


17 


76 


82 


15.. 




27 


60 
60 


1 



1 



100 













Total 







120 


1 


1 


100 


















375 


1,428 


687 


48 


741 


51 











C. SIX CASES CURED IN THREE TREATMENTS. 



103 




7.5 

! io 

| 10 


23 
20 
19 


17 
1.5 
13 


73 
75 
68 


6 
5 
6 


2(1 
25 
31 






62 


45 


72 


17 


27 



January 3, 1913 18 

C. SIX CASES CURED IN THREE TREATMENTS— Continued. 





Case No. 


Age. 


Thymol. 


Worms collected. 




Total. 


Males. 


Females. 




Number. 


Per cent. 


Number. 


Per cent. 


Ill 


10 


Grains. 
20 
20 
20 


449 

22 

3 


266 
11 



59 

50 




183 
11 
3 


40 




Total 


50 
100 




60 


474 


277 


58 


197 


41 






12 




44.. 


10 
10 
20 


113 





55 




48 




58 




51 




Total 








40 


113 


55 


48 


58 


51 






13 




27.. 


20 
20 
30 


122 
25 
23 


56 
12 
9 


45 
48 
39 


66 
13 
14 


54 




Total 


62 
60 




70 


170 


77 


45 


93 


54 






14 




66.. 


20 
20 

25 


54 
8 
10 


28 
4 
5 


51 
50 
50 


26 
4 
5 


48 




Total 


50 
60 




65 

20 
25 
30 


72 


37 


51 


35 


48 






16 




39.. 


369 
162 

7 


183 

68 

3 


49 
41 
42 


186 
94 

4 


60 




Total 


58 
59 




75 


538 


254 


47 


284 


52 












337.5 


1,429 


745 


52 


684 


47 











D. ONE CASE CURED IN FOUR TREATMENTS. 



78 


17 


25 
25 
25 
25 


2,246 

26 

2 

3 


1,048 

W l 



46 

(?) 
50 



1,198 

(? \ 
3 


53 




Total 


(?) 
50 
100 




100 


2,277 


1,049+ 


47 


1,202+ 


53 











E. ONE CASE CURED IN FIVE TREATMENTS. 





10 


12 

15 


54 
11 


40 

5 


74 
45 


14 
6 


25 




54 






12.5 


218 


52 


23 


166 


76 






15 


1 


1 


100 












20 


11 


1 


9 


10 


90 


Total 


74.5 


295 


99 


33 


196 













F. TWO CASES CURED IN SEVEN TREATMENTS. 






24 


12 


20 
20 


109 

267 


49 
91 


44 
34 


60 

176 


55 






65 








20 


53 


15 


28 


38 


71 








25 


24 


6 


25 


18 


75 








25 


36 


10 


27 


26 


72 








25 


8 


2 


25 


6 


75 








25 


9 








9 


100 


Total 


160 


506 


173 


34 


333 


65 






16 




63 


10 
15 


374 
5 


159 
1 


42 
20 


215 
4 


57 






80 








25 


218 


67 


30 


151 


69 








15 























25 


15 


2 


13 


13 


86 








30 


19 


4 


21 


15 


78 








30 


2 


1 


50 


1 


50 


Total 


150 


633 


234 


36 


399 


63 












310 


1,139 


407 


35 


732 


64 









19 



January 3. 1913 



Tabulating the summaries according to the number of treatments,, 
we obtain the following: 





Cases. 


Treat- 
ments to 
cure. 


Worms. 




Total. 


Males. 


Females. 




Number. 


Per cent. 


Number. 


Per cent. 


A 


43 
6 
6 
1 
1 
2 


1 
2 
3 
4 

6 
7 


1,418 
1,428 
1,429 
»2,251 
295 
1,139 


660 
687 
745 
1,049+ 
99 
407 ' 


46 
48 
52 
46 
33 
35 


758 
741 
684 
1,202+ 
196 
732 


52 


B 


51 


C 


47 


D 


53: 


E 


66. 


F 


64 






Total 


'69 


96 


' 7,960 


3,647+ 


46 


4,313 


53: 







' The 58 cases given on p. 14, plus 1 case, in which worms were not found in the stools. 
* Plus 26, sex of which was not determined. 

From these tables it is not evident that the greater the percentage- 
either of males or of females the greater the number of treatments 
necessary. Accordingly/it is not evident that there is any striking 
difference in difficulty in expelling males or females, so far as the. 
number of treatments is concerned. 

Summary. — In view of the statements published in reference to 
the proportion of the sexes in Ancylostoma duodenale, a study of 
the statistics in 102 cases of infection with Necator americanus ia 
distinctly disappointing, and the conclusion seems justified that what- 
ever may be the practical value of estimating the sexes of A. duo~ 
denale, from a standpoint of obtaining a clue as to whether or not 
the cure is complete, this method of procedure, as applied to the 
average hospital case of N. americanus, does not appear to present 
any practical advantage. In fact, the method is much more tedious, 
more time consuming, and less reliable than our present method of 
microscopic examination, and therefore its adoption in our hook- 
worm-eradication campaign is~not to be recommended. 

As a purely academic matter, it is interesting to note that of 
13,080 specimens of Necator americanus collected from 102 cases 46 
per cent of the specimens were males and 53 per cent were females; 
but the proportion for different cases varied, some cases presenting 
more males than females, others more females than males. 

Of 102 cases examined 37 presented an excess of males, 9 presented 
an equal number of males and females, and 56 presented an excess 
of females. 

In 58 cured cases in New Hanover County, N. C, the greatest 
number of worms collected from any one case was 2,277 ; the smallest 
number 1; the average number 135. 

About 75 to 95 per cent of the worms of a given course of treat- 
ment may be passed within 12 hours after the early (6 a. m.) dose 



January 3, 1913 20 

of thymol, and worms may continue to pass for several, apparently 
for at least 6, days following. 

From this latter fact the important practical conclusion may be 
deduced that treatment once per week, as is usual at present, is as 
frequent as it seems either necessary or wise to give it. Treatment 
more often than once a week may be entirely unnecessary, even if 
eggs be found the fifth day after treatment; and since the factor of 
safety to the patient should be constantly held in mind, thymol 
treatment oftener than once a week seems justified only in excep- 
tional cases which may present special features or circumstances that 
indicate the practicability of more frequent dosage.